Researchers at the University of Edinburgh tracked 298 gorillas at zoos in the U.S. and Canada for two decades. On average, the most social and outgoing gorillas outlived the more introverted simians by 3 to 4 years. And the trend carries over into the human world: Extroverted people have been shown to outlive homebodies in recent studies.

Why? The genes in your DNA that control how friendly you are might be near the genes for a stronger immune system or a tougher heart, making you likely to inherit all those traits at once.

Another possibility is that extroverted gorillas and humans use their better social support to deal with stress. "Having somebody who you get along well with may make it easier to cope," study author Alexander Weiss, Ph.D., a psychology professor at the University of Edinburgh, tells MensHealth.com. Reduced stress can mean lower inflammation, less strain on your heart, and better immunity -- just think of how you often get sick after a tough period at work. (Keep stress at bay all day long by following these 19 Ways to Live a Stress-Free Life.)

So what do you do if you're shy? Opening up is just a matter of engaging people the way you want. Here are three ways to build the relationships that might save your life -- on your own terms.

Party on a Deadline

Big gatherings are draining -- and stressful -- for introverts, which may make you want to avoid parties all together. Instead, set an early exit time -- and a graceful excuse -- for yourself in advance. "It paradoxically makes you more social, if you know that you're going to let yourself go home," Susan Cain, author of "Quiet: The Power of Introverts In a World That Can't Stop Talking," tells MensHealth.com.

Chat One-on-One

"When I go to a cocktail party or social event, I look at it not as a room full of strangers, but I'm going to have a series of nice deep one-on-one conversations," says Cain. Instead of approaching the little knots of people already in conversation, sidle up to people you want to chat with who are off by themselves. Bonus: The more focused attention you give, the more likely you are to make a stronger impression.

Speak First

When it comes to brainstorms or meetings at the office, extroverts love bouncing ideas across the conference room tables. Introverts don't. Your fix: Try to be one of the first people to pipe up at meetings -- even if it's simply to agree with something that's been said. "It has a way of shifting positive attention to you early in the meeting, and makes it easier for you to contribute more as the discussion continues," says Cain.